Improvement in hot-air furnaces



2 Sheets--3hee G. W. WHITE.

, Hot-Air Furnaces.

N0.\49,819. l Patented April14,1874.

S e 5.. In/Vew' 2Sheets--Sheet 2. G. w. w HITE.

' Hut-Air Furnaces.

Nol/19,819. Patented April 14, 1874.

W/'nes-ses,

UNITED STATES PATENT GEEICE.

GEoEGE W. WHITE, oE MALDEN, MASSACHUSETTS;

IMPROVEMENT IN HOT-AIR FURNACES.

Specification forming part of Letters Patent No. 149,819, dated April 14, 1874; application filed A March 14, 1874.

To all whom it may concern Be it known that I, GEORGE W. WHITE, of Malden, in the county of Middlesex and State of Massachusetts, have invented'an Improvenient in Hot-Air Furnaces; and I do hereby declare that the following, taken in connection with the drawings which accompany an'dform part of this specification, is a description of my invention sufficient to enable those skilled in the art to practice it.

The invention relates to an improvement in hot-air furnaces, the improvement being particularly designed to increase the heat-radiating surface.

In my construction I combine with the dome of the nre-chamber (and, preferably, with an annular series of pipes leading` from the bottom of said dome up into an annular pipe or chamber encompassing the top of the dome) an auxiliary annular pipe or chamber encompassing the fire-pot, said latter chamber being that into which the products of combustion finally pass before their exit through the main flue-pipe.

My invention consists, primarily, in combination with the furnace or lire-chamber dome, of the annular radiating1 pipe encompassing the ire-pot.

The drawing represents a construction embodying my invention.

Figure 1 shows the furnace in front elevation. Fig. 2 is a side elevation thereof. Fig. 3 is a plan, the upper radiator ring being removed.

a denotes the base 5 b, the ash-pit wall; c, the ash-pit door; d, the lire-pot plate or Wall, c, the iirepot door; f, the dome above the firepot. Extending horizontally from the bottom of the dome are seen the elbow-pipes such pipes .bending and extending up to the radiator-ring h, that encompasses the upper part of the dome, as seen in Figs. 1 and 2. This annular radiator connects with the main vertical flue-pipe t', as seen at 7c; but its connection therewith is controlled by a damper, Z. Around the tire-pot cl is placed the auxiliary radiator-ring m, said ring being joined to the ring h by vertical pipes n n and the ilue-pip'e t', the pipes n n leading from the ring h to the ring m, and the ring m opening into the main vertical line-pipe t'.

When the damper l is open, the products of combustion pass from Vthe dome through the pipes g into the ring h, directly to and through the main flue i; but when the damper Z is closed, the products of combustion pass from the annular pipe h down through the pipes n a, to the annular fire-pot radiator m, through which they pass to the vertical ilue i.

As the auxiliary ring m is in the plane of the lire-pot, it is not only heated by the passage through it of the products of combustion, but is also heated by direct radiation from the :lire-pot plate.

The connecting pipes 0 are placed at uniform distance apart, and such pipes, and the rings h and m and pipes an, constitute aframe that can be set in any position upon the elbowpipes g, to connect with a flue at either side, or at the back of the furnace, the changes of position being in accordance with the number of pipes o.

I claim- In combination with the dome f, the annular radiator pipe m, located in the plane of the fire-pot, and connected by pipes a with the annular pipe h, surrounding the top of the dome, substantially as shown and described.

GEO. W. WHITE.`

Witnesses:

FRANCIS GoULn, M. W. FROTHINGHAM. 

